Drill bit



Sept. 24, 1929. c; g, M, BULL 1,729,063

DRILL BIT I Filed Nov. 26, 1927 2 Sheets-Sheet 1 Qww-nto'o q IZ ' AM? #711. M

Sept. 24, 1929. 1 c. H; M. BULL Filed Nov. 26, 1927 2 Sheets-Sheet 2 n i TE STATE-S @LHTTQN' H. M. BULL, F HOUSTON, TEXAS, AShiIGNOlb TO REED ROLLER BIT COM- PANY, 0F HOUSTON TEXAS, A CORPORATION OF TEXAS isarm. BIT

Application filed November 26, 1927. Serial No. 235,806.

This invention relates to deep well drilling apparatus, and more particularly to drill bits. The invention has for one of its objects the provision of new and improved locking means for the separable parts of a two-piece bit head. 0 Another object is to provide anew and improved roller cutter mounting.

' Further objects will hereinafter appear.

In the accompanying drawings, which are illustrative oft-he preferred embodiment of the invention, Fig. l is a partly sectional side elevation of the assembled bit; Fig. 2, a horiaontal section on the line 21-2 of Fig. 1; Fig. 3, a section on the line 33 of Fig.1; and

Fig. 4, a detail side view of the cutter bushing or support.

Referring more specifically to the drawings, the longitudinally divisible bit head is indicated at 1, the meeting faces of the two partsof said head being recessed for the receptionof a pipe 2 having an annular flange 2 to rest upon the, upper, screw-threaded shank formed by the union of the parts. The

pipe 2 may be held in place by threads 2", or

. otherwise.

The two parts of the head are held together by bolts '3 and 4;, both of which have eyesv t r ough which pipe 2 extends, the meeting ably recessed to receive the enlarged inner ends of said bolts. It will be obvious to those skilled in the art, that when nuts 3 and 4 are tightened, the respective bolts will be moved outwardly to firmly grip the pipe 2, and hold the two parts of the head securely together. And it will be noted that to separate the two parts of the head it is not necessary to remove the bolts. "The bolts needonly be loosened to permit withdrawal of pipe 2, which serves as a locking pin, and the with drawal of which renders the two parts of the head easily separable.

The head may be provided with dowel pins 5 for the guidance oi. the parts'into alignment, and to hold the same against movement with respect to each other.

Keys 6 may be used to prevent rotation of the bolts intheir respective parts.

faces of the two parts of the head being suit It will be understood that any equivalent locking pin ma be, used in place of the pipe sirable because it provides a removable slush or water course through the head toldischarge water upon the cutters andeifect removal of the cuttings.

The head may be spirally grooved as shown at to provide a free upward passage for slush laden with cuttings during drilling operatmns.

The beveled lower ends of the two parts of the head define a substantially V-shaped cutter recess, said ends being provided with integral spindles 8, which project downwardly and inwardly toward the longitudinal axis of the head.

The bushings or cutter supports-8'may be screw-threaded upon spindles 9. Each of these bushings has a cylindrical portion circumferentially grooved as shown at 9, the

side walls of the groove being inclined outwardly to form with tapered sectional ringsv 10 raceways for balls 11. The cutter 12 is provided with opposite racewa s, as shown.-

The parts may be assemble as follows:

The bushing 9is screwed on spindle 8,-and the ointed inner. ends, are then screwed inwardy between said rings. The rings, forced apart by the wedge plugs, force the balls outwardly so that said b'alls enter the raceways in the cutter. The cutter is thus securely and rotatably locked on the busing.

The device disclosed by the drawings and i above described, is the preferred embodiment of the invention, but it is to be understood that various changes may be made within the scope of the following claims.

I claim:

1. A bit head having a plurality of parts, eye bolts secured to said parts, and means extending through the eyes of said bolts to hold I i said parts together.

' 2. A- bit head having a pluralit of parts,

eye bolts secured to said parts, an a plpe extending through the eyes of said bolts to hold said parts together. i

3. A bit head longitudinally divided into a plurality of parts, the lower ends of said parts'being beveled to form a cutter recess, cutters carried by said ends, eye bolts secured to said parts, and means extending through the eyes of said bolts to hold said parts together.

4. -A bit head longitudinally divided into a plurality of parts, the lower ends of said parts being beveled to form a cutter recess,

' to said parts, and a pipe extending through vthe eyes of said bolts. to hold said parts to- I cutters carried by said ends, eye bolts secured gether.

5.v A bit head longitudinally divided 'into two parts, eye bolts carried by said parts, theeyes of said bolts being innermost, and a removable pipe extending through said eyes, 'to hold the parts of said head together, the meeting faces of said parts being recessed for the. reception of said pipe and eyes, 1

6. A bit head longitudinally divided into a two parts, the meeting faces of said parts besignature,

ing recessed to form a central water course,

a removable water pipe in said course, and eye bolts carried by said parts, said pipe extending through said eyes to hold the parts of said head to ether. 1 35 7. A bit hea longitudinally divided into two parts, the lower ends of said parts being beveled to form a cutter recess and having integral spindles thereon extending down wardly and inwardly towardthe longitudinal 1 axis of the head, said parts being grooved to form a central water course communicating with said recess, a removable Water ipe in and course, and eye bolts carried by sai arts, said pipe extending through the eyes 0 said bolts to hold said parts together.

In testimony whereof, I hereunto aflix my 1 Grimm. M.BULL. 

